This shiny penny science experiment is fun for kids of all ages. I love that you can make the pennies look better or worse! You might also enjoy these STEM activities for kids using household items.
Penny Science Experiment for Kids
This simple science experiment is fun, costs pennies, and can be done, reversed, and done again. Pretty magical!
Research Question: Why Does Copper Turn Green?
Have you ever seen a building with a copper roof that was green? The Statue of Liberty is also green because it is made out of copper. This thoroughly confused me as a child, because I knew very well that it was copper that gave pennies their distinct, very un-green color.
Copper turns green after reacting with oxygen. And that green patina actually protects copper from corrosion!
Experiment #1: Pennies and Vinegar
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As an oxidation experiment, we took some shiny pennies and laid them on a vinegar-soaked paper towel. After a couple of days, they turned quite green on the face-up side.
The vinegar only sped up the oxidation of the pennies where the pennies were in contact with the vinegar. The pennies stayed shiny on the side that was against the paper towel.
Science Experiment #2: Pennies and Olive Oil
We wanted to find out if we could then remove that patina.
We took our vinegar pennies and soaked them in olive oil for a couple of days, because I know that’s one way you can clean very old coins.
The “green” side looked a little more metallic, although the pennies definitely showed some marking from their journey.
The “shiny” side actually looked a little worse, especially where a couple pennies had overlapped by accident during the vinegar portion of the experiment!
Have you tried this shiny penny science experiment? What did you discover?
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